The excitation mode refers to the way that the magnetic field is generated in the rotating motor, and the excitation mode of the dc motor is divided into four types:

He excited the dc motor.

Field winding and armature winding without connection relations, and by other dc power supply for power supply of dc motor excitation winding called separately excited dc motor, permanent magnet dc motor can also be used as a separately excited or self excited dc motor, generally called for the permanent magnet excitation type directly.

Shunt dc motor.

The excitation winding of the dc motor is in parallel with the armature winding. As a shunt generator, it is the terminal voltage of the motor itself to supply the excitation winding. As a shunt motor, the excitation winding and the armature share the same power supply, which is the same as that of the dc motor.

Series dc motor.

The excitation winding of series dc motor is connected to the armature winding and connected to dc power supply. The excitation current of this dc motor is armature current.

Compound dc motor.

Compound dc motor has shunt excitation and series excitation winding. If the magnetic flux generated by series winding is the same as that of the excitation winding, it is called cumulative compound excitation. If two magnetic potential directions are opposite, they are called differential compounding.

Dc motors with different excitation modes have different characteristics. Generally, the main excitation modes of dc motor are shunt, series and compound, and the main excitation modes of dc generator are his excitation, shunt and compound.